Method and Apparatus for Real-Time Racket String Tension Measurement

Abstract

A sports racket with racket string tension measurement has a racket frame with a throat that connects a racket head and a racket grip. One or more strings is strung in a stringing pattern, and one or more string anchors retains an end of the string or strings. A tension measurement gauge, such as a strain gauge, is operably associated with the string to sense a tension therein. At least a portion of the tension measurement gauge can be retained by the at least one string anchor, and measured tension can be output to a display. There can be first and second strings strung in a pattern to establish distinct striking zones within the racket head, and tension measurement gauges can be associated with each string. A third string could be strung to establish a peripheral pattern in the racket head.

I claim as deserving the protection of Letters Patent: 
     
         1 . A sports racket with racket string tension measurement, the sports racket comprising:
 a racket frame with a racket head, a racket grip, and a throat that connects the racket head and the racket grip wherein the racket head defines a central opening and wherein a plurality of string holes are disposed through the racket head of the racket frame in spaced relation around a periphery of the racket head;   at least one string with a first end and a second end for being strung through the string holes in the racket head to establish a stringing pattern;   at least one string anchor for retaining one of the first and second ends of the at least one string.   
     
     
         2 . The sports racket of  claim 1  wherein the at least one string is strung through the string holes in the racket frame with main string portions that communicate longitudinally generally parallel to the racket grip and cross string portions that communicate generally perpendicularly to the main string portions and wherein the at least one string anchor retains the first end of the at least one string and wherein the at least one string anchor is disposed at least partially distal to the periphery of the racket head. 
     
     
         3 . The sports racket of  claim 2  wherein the first end of the at least one string is unitarily formed with at least a portion of the at least one string anchor. 
     
     
         4 . The sports racket of  claim 2  further comprising a tension measurement gauge operably associated with the at least one string to sense a tension in the at least one string. 
     
     
         5 . The sports racket of  claim 4  wherein at least a portion of the tension measurement gauge is retained within the at least one string anchor. 
     
     
         6 . The sports racket of  claim 4  further comprising a tension measurement output electrically coupled to the tension measurement gauge. 
     
     
         7 . The sports racket of  claim 5  wherein the tension measurement gauge comprises a strain gauge. 
     
     
         8 . The sports racket of  claim 7  wherein a block of material is fixed over a length thereof to the at least one string and wherein a pattern of conductive material is disposed to communicate along the block. 
     
     
         9 . The sports racket of  claim 6  wherein the tension measurement output comprises a display. 
     
     
         10 . The sports racket of  claim 9  wherein the display is retained by the at least one string anchor. 
     
     
         11 . The sports racket of  claim 1  wherein there are at least first and second strings and at least one string anchor for each of the first and second strings. 
     
     
         12 . The sports racket of  claim 11  wherein a first tension measurement gauge is operably associated with the first string to sense a tension in the first string and a second tension measurement gauge is operably associated with the second string to sense a tension in the second string. 
     
     
         13 . The sports racket of  claim 11  wherein the first ends of the first and second strings are received through string holes immediately outboard of a longitudinal centerline of the racket. 
     
     
         14 . The sports racket of  claim 11  wherein the first and second strings are strung through the string holes in the racket frame with the first string strung to form main strings to a first side of the racket head and cross strings to a proximal portion of the racket head and with the second string strung to form main strings to a second side of the racket head and cross strings to a distal portion of the racket head whereby a stringing pattern with four quadrants is formed with a first quadrant formed in the distal, first side portion of the racket head with main string portions of the first string and cross string portions of the second string, a second quadrant in the distal, second side portion of the racket head composed entirely of main string portions and cross string portions of the second string, a third quadrant in the proximal, first side portion of the racket head composed entirely of main string portions and cross string portions of the first string, and a fourth quadrant in the proximal, second side portion of the racket head with main string portions formed by the second string and cross string portions formed by the first string. 
     
     
         15 . The sports racket of  claim 11  further comprising a third string strung through the string holes in the racket head wherein the third string forms a peripheral pattern in the racket head and the first and second strings form a pattern interior of the peripheral pattern formed by the third string. 
     
     
         16 . The sports racket of  claim 2  wherein the string anchor comprises a base portion and a plurality of string guide sleeves that project from the base portion for being received into string holes in the racket head. 
     
     
         17 . The sports racket of  claim 16  further comprising a tension measurement gauge operably associated with the at least one string. 
     
     
         18 . The sports racket of  claim 17  wherein at least a portion of the tension measurement gauge is retained by the string anchor. 
     
     
         19 . A sports racket with racket string tension measurement, the sports racket comprising:
 a racket frame with a racket head, a racket grip, and a throat that connects the racket head and the racket grip wherein the racket head defines a central opening and wherein a plurality of string holes are disposed through the racket head of the racket frame in spaced relation around a periphery of the racket head;   a first string with a first end and a second end wherein the first string is strung through string holes in the racket head;   a second string with a first end and a second end wherein the second string is strung through string holes in the racket head;   at least one string anchor that fixedly retains the first ends of the first and second strings.   
     
     
         20 . The sports racket of  claim 19  wherein there are first and second string anchors wherein the first string anchor retains the first end of the first string and the second string anchor retains the first end of the second string. 
     
     
         21 . The sports racket of  claim 19  further comprising a tension measurement gauge operably associated with the first string to sense a tension in the first string and a tension measurement gauge operably associated with the second string to sense a tension in the second string. 
     
     
         22 . The sports racket of  claim 21  wherein at least a portion of each tension measurement gauge is retained within the at least one string anchor. 
     
     
         23 . The sports racket of  claim 22  wherein a block of material is fixed over a length thereof to the first string and wherein a pattern of conductive material is disposed to communicate along the block and wherein a block of material is fixed over a length thereof to the second string and wherein a pattern of conductive material is disposed to communicate along the block. 
     
     
         24 . The sports racket of  claim 19  wherein the first ends of the first and second strings are received through string holes immediately outboard of a longitudinal centerline of the racket. 
     
     
         25 . The sports racket of  claim 19  wherein the first and second strings are strung through the string holes in the racket frame with the first string strung to form main strings to a first side of the racket head and cross strings to a proximal portion of the racket head and with the second string strung to form main strings to a second side of the racket head and cross strings to a distal portion of the racket head whereby a stringing pattern with four quadrants is formed with a first quadrant formed in the distal, first side portion of the racket head with main string portions of the first string and cross string portions of the second string, a second quadrant in the distal, second side portion of the racket head composed entirely of main string portions and cross string portions of the second string, a third quadrant in the proximal, first side portion of the racket head composed entirely of main string portions and cross string portions of the first string, and a fourth quadrant in the proximal, second side portion of the racket head with main string portions formed by the second string and cross string portions formed by the first string. 
     
     
         26 . The sports racket of  claim 25  further comprising a third string strung through the string holes in the racket head wherein the third string forms a peripheral pattern in the racket head and the first and second strings form a pattern interior of the peripheral pattern formed by the third string.